The present invention relates to an apparatus and a method for the sterilization of containers. Various methods of this type are known from the prior art and are used for example to sterilize plastics material containers, and in particular plastics material pre-forms, before the further processing thereof. In this case sterilization methods, in which the plastics material containers are subjected to a sterilization agent such as for example hydrogen peroxide or peracetic acid, have long been known. In recent years, however, there has also been a shift towards using electromagnetic radiation, such as for example electron beams, ultraviolet rays or X-rays, for the sterilization. The use of beams of this type conserves resources to a greater degree on the one hand, since additional sterilization agent need not be used, but there is the drawback that hazardous radiation, such as for example ionizing radiation, in particular X-ray radiation, is frequently formed.
For this reason, screening devices are known from the prior art. At present, screens from ionizing radiation, such as for example X-ray radiation, are formed in sterilization plants, for example by rotating or jointly moved radiation separation elements which are arranged between the individual articles to be treated or which are formed by a tunnel-like arrangement of usually vertical separation elements, the dimensions of which depend upon the diameter with respect to the existing arc angle or upon the gap width. The drawback of jointly moved or jointly rotating separation elements of this type lies in the fact that aeration technology is influenced in different ways at different speeds. Furthermore, uncovering can also occur between the ejection faces or transfer faces and, as a result, undesired leaks in the case of rotating separating elements. In addition, in arrangements of this type it is difficult to seal off the beam from separating star wheels and directly at a radiation source of the processing star wheel. Even with narrow divisions between the individual articles to be sterilized, arrangements of this type are problematic. In addition, the assembly is also complicated and a hooking of lost containers can also occur. The provision of a beam tunnel leads to relatively long paths being necessary in part, in order to screen off the radiation. It has been found in this case that X-ray radiation is safe for humans only if it has been deflected or diverted respectively beforehand at least three times.
The object of the present invention is therefore to improve a screening with respect to ionizing radiation, such as in particular X-ray radiation, in the case of apparatus of this type. In addition, however, the outlay for screenings of this type should also be kept low. Ionizing radiation can be electron radiation, UV radiation or, in particular, X-ray radiation.